Method of making boilers



Dec. 15,1925 1555342 f R. `aN. BRCHFIELD METHOD CF .NEAKNT BCI -ERS Filed Au 4, 1923 9; 2 Shams-Shaw l f//Ej/ 'illu' a Dec..15,.1925 1,565,542

R. W. BIRCHFIELD l l METHOD OF MAKING BOILERS l Filed Aug. 4, 1925 2 Sheets-Sheet 2 Patented Dec. l15, 1925i UNITED STATES ROBERT BIECHFIEL'D, OF JULIET, ILLINOIS.

lVIETHOD OF MAKING BOILERS.

Application led August 4,1923. Serial' No, 655,638.

To all whom t may concer/n.'

Be it known that I, ROBERT IV. BIRCH- rinLD, a citizen of the United States, and

resident of Joliet, in the county of-Will and State of Illinois, have invented certain new and useful Improvements in Methods of Making Boilers, of which the following is.

a speciiication.,

My invention relates to'improvements in methods of making boilers and has special reference to improvements inmethods ot making the inside shells of boilers which'x have substantially cylindrical body parts from which water legs depend and provided with auxiliary combustion spaces which rise above the main combustion chambers. Such a boiler is illustrated in my United States-Patent No. 1,398,741.

Thispresent invention has to do especially with the produc-tion of such inside shells for very. large boilers or for boilers of such length that the parts go beyond the capacity of the machines and tools ordinarily pro vided for such work.

usually consists of an inside wrapper which The inside shell, to the production ot which my invention particularly applies,

forms the side walls and crown sheet oi the main combustion chamber, a front plate or head and closure plate at the rear which combines in one member a back plate, a crown sheet for the auxiliary combustion chamber and a flue sheet for the lower lues. It sometimes occurs that the inside wrapper as thus made is longer than the capacity of some of the tools and'particularly than the brake or press for producing the concave -crown sheet and the reverse bends between the' side sheets and the crown sheet, and to meet this condition I have devised-the present method, whereby Il take a sheet of a' width equal to the length of the concave crown sheet being less than the total length of the inside shell by the length of the auxiliary combustion space. I lirst form up this narrow sheet and then I add parts to its rear end t provide the necessary additional length of the side sheets, providing on such additionl part or parts the side sheets, of the anxiliary combustion space, which (rise above the side sheet portions immediately below the concave or main side sheets preierably joining the main: and the auxiliary side sheets by welding.

In making such extension of the -inside 'shell I may add an auxiliary side sheet part tral section of a boiler to each of the main side Vsheets and .then close the space between these auxiliary l arts by oneof my combination back plates, which includes in one member a back plate, an auxassente.

iliary crown sheet and a luesheet, or I mayl take a plate large enough to be capable of being bent to form in one member the two auxiliary side sheets and the whole or major portion of the back sheet.A This back sheet portiony in this construction may extend up to the auxiliary crown sheet oi' it may terminate at a lower point, but wherever it 13er-,l

minates I prefer to close the top with a single member lcombining in one -the lower` rear Hue sheet and theauxiliary crown sheet, and when I desire to make the rear upper part -ot' the auxiliary combustion space', curved on a relatively large radius, I preferably form the auxiliary closure to include the lower rear flue sheet, the crown sheet of the auxiliary combustion space and said curved portion joining the main back plate portion'and the auxiliary crown sheet.

My invention will be more readily understood by reference to the accompanying drawings forming part of this specification and in which:

A Figure 1is a vertical,longitudinal, cenhaving an inside shell made 4.in accordance with my invention.

Figures 2 and 3, are vertical transverse sections of the boiler on the lines 2-2 and 3-3 lrespectively of Figure l.

Figure 4 is a perspective view of the main part of the inner shell, the extension parts of theside sheets-being shown in dotted lines, I

Figure 5 is a perspective view of a completed inner shell,

' Figure 6 is a central, vertical, longitudinal section of the inner shell on the line 6-6 of Figure 5, v`-

Figure 7 is a perspective view of an extension section in which the extension side sheets and a portion of the back plate are made of one piece,

Figure 8 is a perspective view of a com`- bined rear flue sheet, an auxiliary .crown sheet and a portion of the back sheet for use with the part shown in Figure 7 for completing the extension part,

Figure 9 is a perspective view of an extension part some what similar to that shcwn in Figure 7, but slightly modified;l an

Figure 10 is a perspective view of a. part eol drical body portion 2. The body portion 2 is formed of the curved part 3 oflan outer U-shaped shell 4t and the upper curved part 5 of an inner wrapper or shell 6.v The boiler is completed by depending water legs 7 at the sides and forward and rear water legs 8 andl 9 respectively.

lThe water legs are closed at their lower ends by horizontal flanges 10 which may be formed on' the lower edges of the inside wrapper sheet. e The waterlegs enclose a combustion space 'I 11 which extendsthe full length of the boiler and for permitting the gases of combustion to escape therefrom I provide an auxiliary combustion space 12 which ris'es above the rear end of the main combustion space and .admits the gases of combustion into lower t'or'wardly leadingl fiues 13 the gases returning to the rear end of the boiler through the upper longer lines 14.

My invention has partcula" reference to the formation of the inside shell to provide the main combustion space 11 and the auxiliary combustion space 12, especially in extra large or long boilers. c

-In accordance 1with my present invention I provide a flat blank sheet of a length 15 to extend the length'of the main crown sheet portion 5 and said sheet having substantially parallel ends 16. The sheet is wide enough to extend from the lower edge of one side sheet portion 17 up to the crown sheet 5, across the crown sheet and down to the lower edge of the opposite side sheet 17. I first form this sheet to provide the main part of the inside wrapper, as shown in Figure 4, that is the main crown sheet 5 and the deending substantially parallel side sheets 17.

his member may or may not have the bottom flanges 10 formed on the louer edges of the side sheet portions.

As hereinbefore mentioned this present invention has to do with the formation of inside shell for boilers which are so long as to be beyond the capacity of the usual machines and tools and for the purpose of making the inside shell long enough, I proceed to extend the side sheets of the inside shell to provide the auxiliary combustion 'space 12, for this purpose' I may proceed in several4 different ways but in any event I first make the main portion of the tire box with the parallel ends as described and then extend the rear end.

In the preferred form of my invention I provide two extension parts 18-for the side sheets. VThese parts 18 are wide enough to extend from the rear edges of the main side sheet portions to the rear end of the fire box and are long enough 'so that'their u pper end portions 19 extend above `the, Ina-1n crown sheet portion 5 sufficient to form the side auxiliary combustion space and a luesheet` 23 for the auxiliarycombustion space. I

preferably join the edges of the sheets together by welding. The flue sheet portion 27 isprovided with holes 24 to receive thel rear ends of the lower shorter iues 13.

' In Figure 7 I have shown another form of lire box extension.

so In this-case I forma box I like member 25 which is closed on its side f where I desire to make the rear upper cor-- ner 23 of the auxiliary combustion-chamber of relative large radius I preferably cut the back sheet down so that it terminates at its.

upper edge 29 about the bottom of the auxiliary combustion chamber. I close the top of this box like member with a U-shaped member 30 comprising an extension 31 of the back plate 27` a crown sheet 32 and a flue sheet 33 for the auxiliary combustion chamber` This member 32 is preferably joined to the upper edges of the member 25 and to the rear edge of the main c rown sheet by welding and the forward edges of the extentio'n side plates 26 are likewise 'preferably joined the rear edges of the main side sheets 17 by welding resulting in an inner shell as shown in Figure 5.

Instead of cutting down the back sheet 'as shown in Figure 7. I sometimes prefer to leave itthe sameheight as the extension side sheets as shown at 33 Figure 9 whereinl I have shown a fire box extension similar to that already described with this exception.

In this latter instance the top closure is somewhat simpler to make. for as shown in Figure 10 it comprises an L-shaped member 34: which includes a crown sheet 35 and a flue sheet 36 .for the auxiliary combustion ,l chamber.

' In like manner to that already described' close in the auxiliary combustion space including the back plate or rear end of the fire box.

The essential feature is particularly the division of the side plates as indicated in Figure l into the main side sheets which are coincident in length to the main crown sheet, and the extensionside plates which are coincident in length with the length of the auxiliary combustion chamber.

As many modifications of my invention will readily suggest themselves to one skilled in the art I do not limit or confine my invention to the specific steps, or order of steps or specic details of construction herein shown and described. v

I claim:

l1.V The herein described method of forming the inner shell of a boiler which shell includes a main crown sheet, depending side sheets and side sheets for an auxiliary combustion space rising above the main crown sheet, which method comprises forming a main section. oit the shell with a suitable' crown sheet and depending side sheets andattaching extensions to the rear ends of the side sheet portions having, perth-)ns :which extend above the main crown sheet tovr form the side sheets of the auxiliary combustion chamber.

l2. The herein described method of forming the inner shell of a boiler which shell includes a main crown sheet, depending side sheets and side sheets for an auxiliary combustion space rising above the main crown sheet, which method comprises forming a main Vsection of the shell with a suitable crown sheet andde ending side sheets and attaching an extension plateat each side to the rear edge of the depending'side .sheet portions, said extension plates havingparts extending above the main crown sheet to form the side sheets of the auxiliary combustion space.

'3. The herein described V.method of forming the inner shell of a boiler which shelll includes a main crown sheet, depending side sheets and side sheets for an auxiliary com-v bustion space rising above the main crown sheet, which method comprises forming a main section of the shell with a suitable crown sheet and depending side sheets and completing the rear portion of the inner shell by joining to therear edges of the side sheet portions a fire box extension member having parts at the sides extending above the main crown sheet for forming the side sheets of the auxiliary combustion space.

4. The herein described method of forming'an extension for a fire box of the kind described which consists in forming a box like member-open on its top front and bottom, the forward edges o'f the sides being adapted to be joined to the rear edges 'of the main side sheets of a tire box, and closing the top and the upper part of the front by a single plate joined to the top and forward edges preferably by welding.

Signed at Chicago, Illinois, the 31st day of July, 1923.

ROBERT W. BIRCHFIELD. 

